#include "qemu/osdep.h"
#include "qemu/module.h"
#include "hw/i2c/i2c.h"
#include "migration/vmstate.h"
#include "hw/qdev-properties.h"
#include "hw/qdev-properties-system.h"
#include "qapi/visitor.h"
#include "trace.h"
#include "chardev/char-fe.h"
#include "hw/misc/cJSON.h"

#define TYPE_SMC_I2CSLAVE "smc-i2c-slave"
#define SMC_I2CSLAVE(obj) OBJECT_CHECK(slave_state, (obj), TYPE_SMC_I2CSLAVE)
#define I2C_PATH "./output/data/mockdata/i2c/"

static int WRITE_BUFFER_FLAG = 32;
static int READ_FLAG = 33;
static int WRITE_DATA_FLAG = 34;
static int I2C_ADDR = 96;

typedef struct
{
	I2CSlave parent_obj;
	CharBackend chrbe;
	uint32_t count_tx;
	uint32_t count_rx;
	char *path;
	char *key;
	char *msg;			// 通过key值获取的value
	char buffer[10000]; // json文件所有内容
	FILE *p;
	uint32_t reg_bytes;
	uint32_t reg_temp;
	bool write_flag;
	bool transfer_start;
	bool transfer_recv;
	uint8_t reg_id;
	uint32_t opcode;
	uint32_t data[100];		 // 应用层传下来的值
	uint32_t mock_data[100]; // 需要返回给应用层的值
	time_t last_modify;
	struct stat file_stat;
} slave_state;

static int smc_i2cslave_event(I2CSlave *i2c, enum i2c_event event)
{
	slave_state *s = SMC_I2CSLAVE(i2c);
	switch (event)
	{
	case I2C_START_SEND:
		s->transfer_start = true;
		s->transfer_recv = true;
		s->write_flag = false;
		s->count_tx = 0;
		s->count_rx = 0;
		s->opcode = 0;
		s->reg_bytes = 0;
		break;
	case I2C_START_RECV:
		s->transfer_start = true;
		s->transfer_recv = false;
		s->reg_bytes = 0;
		break;
	case I2C_FINISH:
		s->transfer_start = false;
		s->write_flag = true;
		s->count_tx = 0;
		break;
	case I2C_NACK:
		break;
	}
	return 0;
}

static int calc_crc(uint32_t *data)
{
	int crc_table[256] = {
		0x00, 0x07, 0x0E, 0x09, 0x1C, 0x1B, 0x12, 0x15, 0x38, 0x3F, 0x36, 0x31, 0x24, 0x23, 0x2A, 0x2D,
		0x70, 0x77, 0x7E, 0x79, 0x6C, 0x6B, 0x62, 0x65, 0x48, 0x4F, 0x46, 0x41, 0x54, 0x53, 0x5A, 0x5D,
		0xE0, 0xE7, 0xEE, 0xE9, 0xFC, 0xFB, 0xF2, 0xF5, 0xD8, 0xDF, 0xD6, 0xD1, 0xC4, 0xC3, 0xCA, 0xCD,
		0x90, 0x97, 0x9E, 0x99, 0x8C, 0x8B, 0x82, 0x85, 0xA8, 0xAF, 0xA6, 0xA1, 0xB4, 0xB3, 0xBA, 0xBD,
		0xC7, 0xC0, 0xC9, 0xCE, 0xDB, 0xDC, 0xD5, 0xD2, 0xFF, 0xF8, 0xF1, 0xF6, 0xE3, 0xE4, 0xED, 0xEA,
		0xB7, 0xB0, 0xB9, 0xBE, 0xAB, 0xAC, 0xA5, 0xA2, 0x8F, 0x88, 0x81, 0x86, 0x93, 0x94, 0x9D, 0x9A,
		0x27, 0x20, 0x29, 0x2E, 0x3B, 0x3C, 0x35, 0x32, 0x1F, 0x18, 0x11, 0x16, 0x03, 0x04, 0x0D, 0x0A,
		0x57, 0x50, 0x59, 0x5E, 0x4B, 0x4C, 0x45, 0x42, 0x6F, 0x68, 0x61, 0x66, 0x73, 0x74, 0x7D, 0x7A,
		0x89, 0x8E, 0x87, 0x80, 0x95, 0x92, 0x9B, 0x9C, 0xB1, 0xB6, 0xBF, 0xB8, 0xAD, 0xAA, 0xA3, 0xA4,
		0xF9, 0xFE, 0xF7, 0xF0, 0xE5, 0xE2, 0xEB, 0xEC, 0xC1, 0xC6, 0xCF, 0xC8, 0xDD, 0xDA, 0xD3, 0xD4,
		0x69, 0x6E, 0x67, 0x60, 0x75, 0x72, 0x7B, 0x7C, 0x51, 0x56, 0x5F, 0x58, 0x4D, 0x4A, 0x43, 0x44,
		0x19, 0x1E, 0x17, 0x10, 0x05, 0x02, 0x0B, 0x0C, 0x21, 0x26, 0x2F, 0x28, 0x3D, 0x3A, 0x33, 0x34,
		0x4E, 0x49, 0x40, 0x47, 0x52, 0x55, 0x5C, 0x5B, 0x76, 0x71, 0x78, 0x7F, 0x6A, 0x6D, 0x64, 0x63,
		0x3E, 0x39, 0x30, 0x37, 0x22, 0x25, 0x2C, 0x2B, 0x06, 0x01, 0x08, 0x0F, 0x1A, 0x1D, 0x14, 0x13,
		0xAE, 0xA9, 0xA0, 0xA7, 0xB2, 0xB5, 0xBC, 0xBB, 0x96, 0x91, 0x98, 0x9F, 0x8A, 0x8D, 0x84, 0x83,
		0xDE, 0xD9, 0xD0, 0xD7, 0xC2, 0xC5, 0xCC, 0xCB, 0xE6, 0xE1, 0xE8, 0xEF, 0xFA, 0xFD, 0xF4, 0xF3};
	int crc = 0;
	for (int i = 0; i <= data[3] + 3; i++)
	{
		int index = data[i] ^ crc;
		crc = crc_table[index];
	}
	return crc;
}

static void write_buffer(I2CSlave *i2c, char *buffer)
{
	slave_state *s = SMC_I2CSLAVE(i2c);

	s->p = fopen(s->path, "rb+");
	if (s->p == NULL)
	{
		printf("i2c%d open smc file failed\n", s->reg_id);
		return;
	}
	int ret = fseek(s->p, 0, SEEK_END);
	if (ret != 0)
	{
		printf("i2c%d fseek smc file failed\n", s->reg_id);
		return;
	}
	int file_size = ftell(s->p);
	ret = fseek(s->p, 0, SEEK_SET);
	if (ret != 0)
	{
		printf("i2c%d fseek smc file failed\n", s->reg_id);
		return;
	}
	ret = fread(buffer, sizeof(char), file_size, s->p);
	if (ret == 0)
	{
		printf("i2c%d read smc file failed\n", s->reg_id);
		return;
	}
	ret = fclose(s->p);
	if (ret != 0)
	{
		printf("i2c%d close smc file failed\n", s->reg_id);
	}
}

static char *cjson_read_buffer(char *buffer, char *key)
{
	cJSON *root = cJSON_Parse(buffer);
	if (root == NULL)
	{
		printf("parse error\n");
	}
	cJSON *value = cJSON_GetObjectItem(root, key);
	if (value == NULL)
	{
		cJSON_Delete(root);
		return NULL;
	}
	char *msg = (char *)malloc(sizeof(char) * 500);
	msg = cJSON_Print(value);
	cJSON_Delete(root);
	return msg;
}

static void get_mock_data(char *msg, uint32_t *mock_data)
{
	int count = 0;
	int count_num = 2;
	uint32_t verify_data[100] = {I2C_ADDR, READ_FLAG, I2C_ADDR + 1}; // 计算crc验证码的数组
	char str[4] = "0x";
	for (int i = 0; i <= strlen(msg); i++)
	{
		if (msg[i] == '"')
		{
			count++;
		}
		if (msg[i] == '"' && count >= 3 && count % 2 == 1)
		{
			str[2] = msg[i + 1];
			str[3] = msg[i + 2];
			char *pEnd;
			mock_data[count_num] = (uint32_t)strtol(str, &pEnd, 16); // 转16进制
			count_num++;
		}
	}
	mock_data[0] = count_num - 1;
	mock_data[1] = 0;
	for (int i = 0; i < count_num; i++)
	{
		verify_data[i + 3] = mock_data[i];
	}
	mock_data[count_num] = calc_crc(verify_data);
}

static void change_value(cJSON *value, char *msg, uint32_t *data)
{
	char str[3] = {0};
	int count_str = 3;
	int count_num = 6;
	for (int i = 0; i < data[1] - 4; i++)
	{
		snprintf(str, 3, "%02x", data[count_num]);
		cJSON_ReplaceItemInArray(value, count_str, cJSON_CreateString(str));
		count_str++;
		count_num++;
	}
}

static void change_json_buffer(I2CSlave *i2c)
{
	slave_state *s = SMC_I2CSLAVE(i2c);
	cJSON *root = cJSON_Parse(s->buffer);
	if (root == NULL)
	{
		printf("parse error\n");
	}
	cJSON *value = cJSON_GetObjectItem(root, s->key);
	if (value == NULL)
	{
		error_report("the key is error\n");
	}
	change_value(value, s->msg, s->data);
	char *new_json_str = cJSON_Print(root);

	s->p = fopen(s->path, "w+");
	if (s->p == NULL)
	{
		printf("i2c%d open smc file failed\n", s->reg_id);
		return;
	}
	int ret = fwrite(new_json_str, strlen(new_json_str), 1, s->p);
	if (ret == 0)
	{
		printf("i2c%d write smc file failed\n", s->reg_id);
		return;
	}
	ret = fclose(s->p);
	if (ret != 0)
	{
		printf("i2c%d close smc file failed\n", s->reg_id);
	}
	memset(s->buffer, 0, sizeof(s->buffer));
	strcpy(s->buffer, new_json_str);
	if (stat(s->path, &s->file_stat) == 0)
	{
		s->last_modify = s->file_stat.st_mtime;
	}
	cJSON_Delete(root);
}

static uint8_t smc_i2cslave_rx(I2CSlave *i2c)
{
	slave_state *s = SMC_I2CSLAVE(i2c);
	int rx = s->mock_data[s->count_rx];
	if (s->count_rx > s->mock_data[0] + 1)
	{
		return 0;
	}

	s->count_rx++;
	return rx;
}

static int smc_i2cslave_tx(I2CSlave *i2c, uint8_t data)
{
	slave_state *s = SMC_I2CSLAVE(i2c);
	uint32_t opcode_mask = 0xfffffc00;
	s->data[s->count_tx] = data;
	if (s->count_tx == 5 && s->opcode == 0)
	{
		s->opcode = (s->data[2] << 24) + (s->data[3] << 16) + (s->data[4] << 8) + s->data[5];
		s->opcode = s->opcode & opcode_mask;
		s->key = g_strdup_printf("0x%08x", s->opcode);
		s->write_flag = true;
		if (stat(s->path, &s->file_stat) != 0)
		{
			error_report("Get timestamp from %s failed;\n", s->path);
		}
		else if (s->file_stat.st_mtime != s->last_modify)
		{
			warn_report("Detect %s changed, Reload buffer;\n", s->path);
			write_buffer(i2c, s->buffer);
			s->last_modify = s->file_stat.st_mtime;
		}
		s->msg = cjson_read_buffer(s->buffer, s->key);
		if (s->msg == NULL)
		{
			g_free(s->key);
			s->write_flag = false;
			s->count_tx++;
			return -1;
		}
	}

	if (s->data[0] == WRITE_BUFFER_FLAG && s->write_flag == true)
	{
		get_mock_data(s->msg, s->mock_data);
		free(s->msg);
		g_free(s->key);
		s->write_flag = false;
	}

	if (s->data[0] == WRITE_DATA_FLAG && s->write_flag == true && s->count_tx - 2 == s->data[1])
	{
		change_json_buffer(i2c);
		free(s->msg);
		g_free(s->key);
		s->write_flag = false;
	}
	s->count_tx++;

	return 0;
}

static void smc_i2cslave_reset(DeviceState *dev)
{
	slave_state *s = SMC_I2CSLAVE(dev);
	s->transfer_start = false;
}

static void smc_i2cslave_realize(DeviceState *dev, Error **errp)
{
	slave_state *s = SMC_I2CSLAVE(dev);
	s->path = g_strdup_printf("%s%d/0x60_smc.json", I2C_PATH, s->reg_id);
	s->transfer_recv = false;
}

static void generic_i2cslave_access_addr(Object *obj, Visitor *v, const char *name, void *opaque, Error **errp)
{
	uint8_t *ptr = (uint8_t *)object_field_prop_ptr(obj, (Property *)opaque);
	visit_type_uint8(v, name, ptr, errp);
}

static const PropertyInfo generic_i2cslave_prop_regaddr = {
	.name = "uint8",
	.get = generic_i2cslave_access_addr,
	.set = generic_i2cslave_access_addr,
	// .realized_set_allowed = true,
};

static Property smc_i2cslave_properties[] = {
	DEFINE_PROP_UNSIGNED_NODEFAULT("reg-id", slave_state, reg_id, generic_i2cslave_prop_regaddr, uint8_t),
	DEFINE_PROP_END_OF_LIST(),
};

static void smc_i2cslave_class_init(ObjectClass *klass, void *data)
{
	DeviceClass *dc = DEVICE_CLASS(klass);
	I2CSlaveClass *k = I2C_SLAVE_CLASS(klass);
	k->event = smc_i2cslave_event;
	k->recv = smc_i2cslave_rx;
	k->send = smc_i2cslave_tx;
	dc->reset = smc_i2cslave_reset;
	dc->realize = smc_i2cslave_realize;
	device_class_set_props(dc, smc_i2cslave_properties);
}

static void smc_i2cslave_init(Object *obj)
{
	slave_state *s = SMC_I2CSLAVE(obj);
	s->transfer_start = false;
}

static const TypeInfo smc_i2cslave_info = {
	.name = TYPE_SMC_I2CSLAVE,
	.parent = TYPE_I2C_SLAVE,
	.instance_size = sizeof(slave_state),
	.class_init = smc_i2cslave_class_init,
	.instance_init = smc_i2cslave_init,
};

static void smc_i2cslave_register_types(void)
{
	type_register_static(&smc_i2cslave_info);
}

type_init(smc_i2cslave_register_types)